An explosion in the boiler of Unit 5 at the Lethabo Power Station near Viljoensdrif in the Free State last week has put Eskom’s already stressed supply under further pressure.

One employee was killed in the explosion and another was injured.

“Based on the preliminary investigation, it is expected that Unit 5 will remain out of service for a minimum of three months,” Eskom group chief executive, Phakamani Hadebe, said in a statement. “This will have a negative effect on the power system given that Lethabo Power Station is one of the most cost-effective generators with adequate access to a steady coal supply.”

Currently Eskom does not have sufficient coal supply at 10 of its 15 power stations.

According to the energy company, loss of supply from Tegeta has resulted in a shortfall of 713 kilotons per month or 8.5 million tons per annum.

“To manage the situation at Tegeta-affected power stations – namely Hendrina, Komati and Majuba – Eskom had to transfer coal away from stations with healthy stock levels,” a statement from Eskom read.

Additionally, Eskom noted that the industrial action taken by staff during July and August had exacerbated the low stock levels.